Acoustic communication is widespread among animals. Despite a strong research focus on how the nervous system generates vocal behaviour, interactions between the nervous system, morphology and the environment are often overlooked. However these interactions are critical in understanding how neural signals (brain) are translated into acoustic signals (behavior).
Birdsong is among the most successful model systems for answering fundamental questions in behavioral neuroscience. It has been especially productive in identifying the neural mechanisms underlying imitative vocal learning as found in human speech acquisition. While we also use comparative approaches, we focuss on the best-studied model species: the Australian zebra finch. Instead of working ‘from the brain down’, our aim is to define neuromuscular control parameters and constraints by understanding the biomechanics of sound production to answer the fundamental question:
“How is neural activity translated into sound?”
We use a variety of in vivo, ex vivo and in vitro experimental physiological techniques combined with various forms of (high-speed) imaging. Furthermore, we use a comparative approach and study sound production mechanisms and control across the vocal vertebrates, such as other bird species, bats and fish.
Skeletal muscles working at cycle frequencies over 100 Hz were previously considered extremely rare adaptations. Our research has recently established the presence of superfast muscles in (song)birds (Elemans et al, Nature 2004; PLoS ONE 2008) and mammals (bats, Elemans et al., Science 2011). These results show that these muscles are present across the vertebrates, all in the context of sound production. We are currently studying 1) the function and cellular mechanisms underlying superfast muscle design in a comparative context and 2) the evolution of the superfast muscle motor protein, myosin, using a genomic approach. Next to their pivotal role in sound production, superfast muscles act as an excellent model system to study basic muscle physiology.